Tunnel Drainage Pipeline for Swiss highway in Knonaueramt
The 4.95 km long tunnel consists of 2 sections each of which hold a 7.75 m wide road and 1 m banquets on each side. An accessible service channel dimensioned 3.20 x 2.05 m runs below the road. For safe tunnel drainage and along with other tunnel equipment, it holds a 10.4 km HOBAS CC-GRP TunnelLine® System of DN 200 to DN 400, SN 2500 to 10000. The pipe delivery for the relatively narrow service channel was well planned by HOBAS. The comparably light CC-GRP Pipes were packaged to perfectly fit through the channel where they could easily be unloaded by 2 men. To provide an optimal drainage, the pipes were brought into a constant gradient and assembled with the help of a small crane. In addition to the standard HOBAS Couplings that are readily mounted on one end of each pipe, mechanical couplings were installed at two points of the line. They were necessary since the pipeline was built beginning from both sides of the tunnel. Furthermore they can be easily opened for pipe inspection.